Cylinder-boring machine



May 11 1926. 1,583,786

A. F. FROUSSARD CYLINDER BORING MAHINE Original Filed May 2, 1921 3 sheets-Sheet 1 -HgL a 49 4s 47 as lNVENTOR mmoussmo May 11 ,1926. v 1,583786 -A.' F. FROUSSARD CYLINDER BORING MAGI'IINIEJ Original FiledMay 2. 1921 3 Sheets-Sheet 2 Fig.6.

INVENTOR F.FROUSSARD ATTORNEY A. F. FROUSSARD IIIIIIIIIIIIIIIIIIII E.

. NTOR- A.F.F SSARD BY k flm I ATTORNEY Patented May 11, 1926. i

UNITED STATES PATENT; OFFICE;

ALBERT r. rnonssann, or s11. LOUIS, MISSOURI.

CYLINDER-BORING MACHINE.

Application filed May 2, 1921, Serial No. 466,146. Renewed October 14, .192 5Q simple and effective means for centering the boring bar so as to rebore the cylinder exactly concentric with the original bore. Another object of my invention is to provide improved means for adjusting the cutters ofv the boring head. My invention also con.-

sists in various novel features and details of construction.

In the accompanyingdrawings which illustrate one form of device made in accordance with my invention, together with certain modifications thereof Figure 1 is a vertical central section; Figure 2 is a section of the cutter head; Figure 3 is an enlarged section of one side of the cutter head showing the parts-in a different position; Figure l. is partly a plan view and partly a section of the cutter head and boring bar; Figure 5. is a vertical central section through the lower part of the device showing the centering means in position Figure 6 is partly a :lan view and partly a. section of the centering means; Figure 7 is a topplan view; Figure 8. is an enlarged-top view showing a star wheel. for feeding the cutter head; Figure 9 is a view partly in plan and partly in section, showing a modified form of centeri'ng device; Figure 10 isa, vertical section Showing a. modifi'cation of -the cutter head and centering device-and Figure 11 is an enlarged sectional view of" the central part of. the, centering device shown in FigurelO. The driving headiof my device consists two. casings 1 and-2 secured together by means of bolts, 3, one of, which also secures position a vertical bar 4- forming a stop for the feeding device. as will be hereinafter described. Contained in the driving head is a worm wheel 5 driven by pulley 6 adapted to receive a belt andv also preferably provided with a handle, 7 as shown in Figure 1 so that'the device be driven: by the hand if power is not available, The worm 5 meshes with a worm wheel 8 surrounding the boring bar 9. 10 are bearings situated one at each side of the worm wheel, Sand both preferably of conical form and inclined in the same direction so as to compensate for wear. Anti-friction bearings 11 are preferably used to take up the end thrust. The worm wheel 8 is secured to the boring I segments.

bar 9 by means of a safety set screw 12'and access is given to said screw by means of a removable plug 13- in the part 1 of the casing so that the boring bar be slid longitudinally in the boring head as will be here: inafterdescribed. Carried at the lower end of the part 1 of the boring head are a pair of slotted arms 14.. 15 are L-shaped spacing and fastening blocks, one arm of each of which is adapted to be secured to one of the slotted arms 14 by means of'abolt 16' and the other. arm is adapted to bejsecured by means of; a bolt 17 to the upper end of the cylinder 18 which is to be bored.

The centering device shown in Figures. 5 and .6 consists of a central part 19 adapted to snugly fit the boring bar 9 and provided at its lower end with a conical face 20 and at its upper end with a straight externally threaded portion 21. The, outer or expansiblepart of the centering. device consists of seg'ments22, preferably six in number, havments 22 are held in position around the part 19 by means of a. coil spring 23 ar ranged in a suitable annular groove. 24: is an adjusting nut engaging with the part 21 andadapted to move the segments 22 longitudinally so as to expand thein against ing their inner faces shaped to correspond with the exterior of the part 19. These seg the exterior of the cylinder 18. In order to secure'the exact'centering of the device, it is necessary that thesegments 22 be prevented from moving around the part 19. This, accomplish by setting. in the said part 19 ,Voodruft keys corresponding in. number to the segments 22 and sliding in ways or slots 26 formed in the inner tapering facesof said I in using mydevi'ce, thecentering device is first placed in the upper part of the cylinder as shown in Figureb. The adjusting nut 24 is turned down until the segments of the cylinder thus centering the sleeve 19. The boring baris now passed downthrou ,h thersleeve 19 and, the driving head's firm-y fastened in position by means ofv the fastening, and spacing blocks 15' so as to insure the proper centering of the boring bar 9. The nut 24 can now be loosened soas to allow the centering device to pass out through the bottom of the cylinder and the device operated to bore the cylinder as. will be hereinafter more fully set forth. In case the are forced firmly againstthe inner wall lower end of the cylinderis obstructed so it is not possible to remove the centering device in this manner, the set screw 12 may be loosened so as to allow the boring bar to be moved longitudinally in the boring head to release it from the centering device which may now be removed through the space between the upper end of the cylinder and the driving head. The space blocks 15 should therefore be of such size as to insure sufficient space for this purpose. The cutter head is placed between the two parts and the boring bar lowered to engage the same.

Owing to the length of the bearings 10 it will not usually be necessary to provide additional supporting means for the boring bar. WVhen, however, long cylinders are to be bored it may be advisable to provide a lower supporting bar 27 as shown in Figure 1, which bar is provided with a center point 28 adapted to enter a conical bearing center in the lower end of the boring bar. This support 27 is secured in position on the lower end of the cylinder by means of bolts 29 passing through slots 30 on the said bar. My preferred form of cutter head which 1s shown in Figures 1 to 5 inclusive, comprises a sleeve 31 accurately fitting the boring bar 9. and provided with an internally threaded lug 32 sliding in a corresponding groove 33 in the boring bar and engaging with the threaded feed rod 34. Surrounding the sleeve 31: is a collar 35 secured thereto by means of a set screw 36 (Figure 5). The exterior of the collar 35 is threaded to re ceive a pair of locking nuts 37 which nuts are adapted to bear against the cutting tools 38. These tools 38 are preferable six in number, and are situated in tool slots in the said collar 35. The sleeve 31 is provided with corresponding tool slots 39 so that the tools may be moved inwardly into the position shown in Figure 3. The inner ends of the tools are beveled as clearly shown in Fig vu're 3 and these beveled faces are adapted to be engaged with the upper beveled edge of a flange .40 carried on an adjusting. nut 41.

This flange 40 passes between the sleeve 31 and the lower part of the collar 35 which is spaced from the sleeve as clearly shown in Figures 3 and 5 to receive this flange and have threaded engagement therewith. It will be evident that by rotating the nut 41 so as to move the flange upwardly, the tools 38 will be forced outwardly. A locking nut 42 is used to look the adjusting nut in position after the proper adjustment of the tools is secured.

The upper end of the rod 34 is carried in a bearing 45 situated in the slot 33 and is adapted to receive a handle 46 for rotating the said rod to move the cutter head by hand. The feed rod is provided with a key 47 adapted to engagewith a disc 48 to which a feedarm 49 is pivotally secured by means of a screw 50, said feed arm being adapted to bear against the feed bar 34 and the feed stop as shown in Figure 7. WVhen the parts are in this position the feed bar will be prevented from rotating while the cutter bar is rotated and consequently the cutter head will be fed forward the distance of one thread on the feed bar for each rotation of the cutter bar. When a slower feed is desired, the feed disc 48 is removed and the star wheel 51 shown in Figure 8 is substituted therefor. ranged that two or more arms may be used by engaging the different key ways in said arms with the key 47 so that the number of effective arms will be varied.

In Figures 9, 10, and 11 I have shown slight modifications of my device.' In the form shown in these figures, the centering device in place of engagement with the interior of the cylinder itself engages with the piston rod opening. In this form of device the central conical plug 52 is provided with a center point 53 adapted to engage with the lower end of the cutter bar 9. The outer expansible part consist of segments held in position by a coil spring 55 and prevented from rotating relative to the part 52 by means of Woodrufl keys 56. It

will be seen that this kindof centering device while differing slightly in form from that above described is substantially the same in operation except that it remains in position during the operation of the boring bar instead of being removed to make place for the boring head. When this form of centering device is used I prefer to provide the plug 52 with an oil passage 58 connected by a suitable pipe 59 with an oil supply so as to lubricate the center point 53 during the operation of the device.

In Figure 10, I have also shown a modified form of cutter by means of which the ends of the cylinder may be counter-bored. In this form of boring head a cylindrical block 61 surrounds the boring bar 9 and is provided with a threaded lug corresponding to the lug 32 hereinbefore described and engaging with the feed rod 34. The lug 60 carries a recessing tool 62 adapted to be adjusted radially by means of a screw 63 and secured in position after adjustment by a screw 64. As these screws may be reached from the upper end of the cylinder by means of a suitable wrench, it will be evident that the tool can be radially adjusted to counterbore the end of the cylinder while the tool is in position.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a device of the class described, the combination with a boring bar, of a driving head for said bar, means for securing said driving head to a cylinder, and a centering device for said'bar, said centering device This star wheel is so ar- I comprising a sleeve surrounding said bar and provided at one end with a conical por tion and at the other with a threaded portion, a nut on said threaded portion, and an expansible collar surrounding said sleeve and engaging at one end with said conical portion and at the other with said nut, the periphery of said collar being adapted to engage with the interior of a'cylinder'ol larger diameter than said sleeve and nut.

2. In a device of the class described, the combination with a boring bar, of a driving head for said bar, means for securing said driving head to a cylinder, and a centering device for said bar, said centering device comprising a sleeve surrounding said bar and provided at one end with a conical portion and at the other with a threaded portion, a nut on said threaded portion, and an expansible collar surrounding said sleeve and composed of a plurality of segments situated between said nut and conical portion, and resilient means for retaining said segments in position, said means being situated in an annular groove in the bearing face of the collar.

3. In a device of the class described, the combination with a boring bar, of a driving head for said bar, means for securing said driving head to a cylinder, and a centering device for said bar, said centering device comprising a sleeve surrounding said bar and provided at one end with a'conical portion and at the other with a nut, an expansible collar surrounding said sleeve and consisting of a plurality of segments situated between said conical portion and nut but projecting beyond the same, and keys for preventing the relative rotation of said segments.

4:. In a device of the class described, the combination with a boring'bar, a cutter head for the bar, a threaded rod eccentrically mounted in said boring bar for moving said cutter longitudinally, a member non-rotat-. ably carried by said rod, an arm pivoted to said member and adapted to bear against said rod, and a stop adapted to contact with said ar 5. In a device of the class described, the, combination with a boring bar, of a cutterhead for the bar, a threaded rod eccentrically mounted in said boring bar for moving the cutter longitudinally, a member non-rotatably carried by said bar, an arm pivoted to said member and adapted to bear against said rod, a star wheel interchangeable with said arm, and a stop adapted to actuate the feed mechanism.

In testimony whereof, I have hereunto set 'my hand and affixed my seal.

ALBERT F. FROUSSARD. [L. s.] 

